This application claims priority from U.S. Provisional Application Ser. No. 61/374,774 filed Aug. 18, 2010.
The present invention relates to fire protection, and, in particular, to a device and method for protecting against fire in a container or unit load device (ULD) in the cargo hold of a vessel, such as an aircraft, railcar, or ship.
Goods to be transported in a vessel, particularly goods to be transported via aircraft, are usually loaded into containers (typically referred to as unit load devices (ULD's)), which are then loaded onto the vessel, in order to facilitate and speed up the loading and unloading process. It is possible for something in a ULD to ignite, with the smoke and heat of the fire being contained in the ULD, until it suddenly and explosively breaks out of the ULD and into the cargo hold. At that point, the fire could spread rapidly, which would create a dangerous situation.
While vessels currently have fire alarm and protection systems, those systems often do not sense the presence of a fire that is contained inside a container or ULD, which means that a fire could be smoldering for quite a while before it is detected, and, by the time it is detected, it may be such a large fire that it is difficult or impossible to suppress. For that reason, it would be desirable to modify or add to the existing systems to make them more effective at detecting and suppressing fires in containers or ULDs. However, modifications to an aircraft typically require full approval and recertification by a number of agencies which may include the aircraft manufacturer, the Federal Aviation Administration, and the US Department of Transportation, among others. There is also a concern about adding weight to the aircraft due to the modification, the cost of the modification itself, and the time required to install, and eventually to test and maintain, the modification.
It would be desirable to provide a device and method for automatically suppressing a fire inside a container (such as a ULD) while simultaneously alerting the fire alarm systems of the vessel, preferably without tying in electrically or mechanically, or otherwise in any way modifying the aircraft such that recertification is required. It would be preferable for such an automatic fire suppression and alarm system to be a totally passive system requiring no outside power (again, no tying into the aircraft systems) and no self-contained electrical power supply which has to be charged and which could, itself, be an ignition source.